ΔABC is similar to ΔDEF. The ratio of the perimeter of ΔABC to the perimeter of ΔDEF is 1 : 10. If the longest side of ΔDEF measures 40 units, what is the length of the longest side of ΔABC ?

2 units
4 units
16 units
30 units

Question

ΔABC is similar to ΔDEF. The ratio of the perimeter of ΔABC to the perimeter of ΔDEF is 1 : 10. If the longest side of ΔDEF measures 40 units, what is the length of the longest side of ΔABC ?

2 units 
4 units 
16 units
30 units

anonymous · Answer

DEF is 10 times bigger

anonymous · Answer

Which means 40 units is 10 times bigger than the answer

anonymous · Answer

40/10

anonymous · Answer

if the perimeter is 10 times bigger, that means each side is 10 times bigger as well. 
the answer is 4